\subsubsection{System tray icon}
(Partly depricated information) System tray icon is a small icon that is usually displayed in notification area. \texttt{SystemTrayIcon} class implements this icon and it's pop-up menu, which allows user to manage Entertainer media center. Pop-up menu contains Log viewer, which can be used to see Entertainer's log. It also allowes easy way to execute configuration GUIs and frontend process. SystemTrayIcon class implements MessageHandler and it is interested of messages \texttt{RECORDING\_STARTED} and \texttt{RECORDING\_STOPPED}. When Entertainer is recording a TV-show the system tray icon changes to the recording icon. This way user can easily see that Entertainer is currently recording.

\subsubsection{Notification system}
Notification system displays notification bubbels on the desktop. Notification system is implemented with \texttt{Notify} class that uses \emph{libnotify} library. Notification bubbles are displayed when Entertainer backend begins or ends recording and also if there are conflicts between scheduled recordings. It's easy to add new notifications by modifying the \texttt{Notify} class. \texttt{Notify} implements \texttt{MessageHandler} and it's registered to the message bus when backend starts.

\subsubsection{Feed manager}
Feed manager is responsible of updateing feed cache. At the moment, only RSS-feeds are supported. \texttt{FeedManager} and \texttt{FeedFetcher} classes implements this feature. \texttt{FeedManager} implements \texttt{MessageHandler} interface and it is registered to the message bus. When \texttt{FeedManager} receives \texttt{UPDATE\_FEEDS} message, it executes a new \texttt{FeedFetcher} thread that does the actually cache updating. When update is done, \texttt{FEED\_CACHE\_UPDATED} message is emitted to the message bus.
